Show organizers said there will be 3,200 exhibitors and they expect 156,000 visitors -- matching the record number that attended in 2012. Last year, there were about 3,000 booths, but Microsoft said afterwards it would withdraw from the event after years of attending.

Like Google and Apple, Microsoft has decided it will rely primarily on its own events to promote its products, which doesn't deter CES with its array of small and large companies -- many that will come to meet with partners and suppliers in private rooms both inside the exhibit hall and in remote hotels.

Even without a booth, Microsoft is holding meetings with reporters, partners and suppliers in private spaces, Microsoft and CES officials confirmed.

"A handful of large companies like Microsoft will do what they want and they'll surely get attention," Dunion said. A special area for exhibitors new to CES called Eureka Park will have 140 vendors, up from 100 last year, she said.

Microsoft's booth absence means there probably won't be official word of the exact date that the Windows 8 Surface Pro tablet ships, although it has been promised for late January, say several analysts.

In general, smartphones and tablets will again be big news at CES this year, although to a lesser extent than two years ago or last year, according to four analysts. In 2011, Verizon Wireless announced half a dozen smartphones and tablets it would sell, but this time is not expected to be making similar hardware news even though Verizon CEO Lowell McAdam is delivering a keynote on Tuesday.

CES said in December that about 1,500 of the exhibitors will be showing off wireless-related products, which go far beyond smartphone and tablet hardware to include ways to integrate handheld wireless devices -- often simply through embedded chips -- with cars and homes. Connecting data on wireless devices to the cloud will be another theme of wireless vendors.

Whether the tablet and smartphone hardware news at CES is considered as hot as it was in recent years, the economic potential for both product categories remains huge. Research by the Consumer Electronics Association shows that smartphones alone will remain the "primary" revenue driver for the entire consumer electronics industry in 2013 (including TVs and many other areas), with a 16% increase over 2012 of smartphones shipping to retailers (reaching 125 million devices) and driving $37 billion in global revenues.

The association also believes tablet shipments will soar by 54% in 2013 over last year to 105 million devices, creating $35 billion in revenue.

The emergence of the WiGig standard will mean that some exhibitors show off ways at CES to transfer video and music at speeds of 7Gbps within the space of a living room, for example. (In a related development, the WiMax Alliance announced a merger with the Wireless Gigabit Alliance on Thursday.)

Also at CES, Intel is promising to announce updates for chips for both smartphones and tablets at a Monday press event, a spokeswoman said on Thursday.

There are persistent rumors as well that Lenovo will announce a smartphone running on an Intel Atom processor later in the week at CES, although a spokeswoman said Lenovo would not comment on those rumors. Intel showed off a prototype of an Atom-based smartphone at last year's CES, without disclosing potential vendors.

The emergence of Intel-based processors for smartphones has been slow in coming, while Android and iOS have dominated the market with ARM-based devices.

"Intel chips are in fact quite good, but Lenovo as a brand here in the U.S. is not the biggest brand for smartphones," said IDC analyst Ramon Llamas.

Meanwhile, more Android tablets and smartphones from Samsung, LG and others should be unveiled when the show kicks officially for four days on Wednesday. (Several vendors will offer press events even earlier, starting Sunday.)

As for smartphone particulars, four analysts said they expect larger screens, with at least one new smartphone expected to top 6-in. "That's a huge smartphone," said Ramon Llamas. By comparison, the iPhone 5 sports a 4-in. screen, up from the 3.5-in. of earlier versions.

There's also been talk of smartphones running not only dual- or quad-cores, but octo-cores, Llamas said. A big theme with Android devices will be those that run the new generation Android OS, called Jelly Bean.

While many smartphone vendors will push larger and faster devices, Llamas said, "I'm kind of done with the spec war." A theme of CES will be about usage cases for various devices, including a wider promotion of applications to support new uses.

Llamas said that means vendors should, and will, talk about the kinds of experiences they can offer with smartphones and tablets, such as how to use Near-Field Communication (NFC) or augmented reality with a handheld device.

Nokia has talked about using augmented reality in conjunction with its Lumia line of smartphones, offering the example of a user holding up a phone to a street filled with stores. In the smartphone's display, the augmented reality will take advantage of GPS information and identify the various stores and restaurants within view, with their names superimposed over the phone's image of the storefront.

What will happen in future generations of augmented reality is that a user can drill down on that information, accessing data on the menu served at a restaurant seen in the display, and also seeing reviews by prior customers. Llamas said he expects Qualcomm and Intel chips to support this level of functionality in smartphones and tablets in 2013.

"Augmented reality will be the place to be for vendors for 2013, moving it past novelty-ware and entertainment," Llamas said. "Nokia has been a frontrunner."

Gartner analyst Carolina Milanesi said that CES 2013 will also continue the trend of the "blurring of the line between smartphones and tablets," in the same vein as the Samsung Galaxy Note II, with its digital stylus and its 5.5-in. screen.

Called "phablets" by many for combining a phone with a tablet, Huawei is expected to show off the Ascend Mate at CES, featuring a 6.1-in. screen and a quad-core chip and a phone. Gizmodo notably called it a "monster," adding, "Where will this hugification finally end? Apparently not at half a foot."

Several analysts said that vendors have to be wary not to make users laugh or reject their phablet inventions. "I still believe those in-between devices have too much compromise for most users," Milanesi said.

The big trends for actual tablets sans phones at CES will be higher resolution screens and lower prices, several analysts said. "You'll see high definition displays even on low cost tablets, and Android tablets for under $150 from Asian manufacturers mainly," said Bill Rom, a consultant for 151 Advisors.

What Rom hopes will emerge at CES is some broader recognition of the needs for greater security and privacy as wireless network speeds and device processor speeds increase.

"I don't know that enough is being done with privacy and security protections, and so far there's not been a big enough of a security breach to push the need as high as it should be," Rom said. "I suppose vendors don't want to scare people from buying stuff."

CES will actually feature security and identity software vendors as well as an array of applications for smartphones and tablets. In general, analysts including Milanesi expect less of an emphasis on hardware than in recent years with more of an emphasis on software, applications and uses of hardware in various network settings.

CES spokeswoman Dunion said that CES 2013 will actually house the "world's largest app show," bringing in more apps vendors than in 2012 and showing off apps that offer a little of everything.

As for the absence of Microsoft at CES, analysts agreed with CES officials that it won't probably do much to hurt the trade show and should actually help Microsoft.

"I don't think it will matter whether Microsoft has a booth at CES," Rom said. "They always have their own events and their own launches and are focused on building out their own ecosystem. The problem for Microsoft will still be getting developers interested in consumer apps" for Windows Phone and Windows 8 tablets.

However, Jack Gold, an analyst at J. Gold Associates, said the absence of Microsoft at CES in 2013 raises questions for CES and other major trade shows that cover many technologies well beyond wireless -- including digital TVs and more -- as trade show promoters seek out a multiplicity of vendors, small and large, to purchase booth space.